From Japanese Published, Nonexamined Patent Application 9-103052, a production method for the stator of an electrical machine.
For producing this stator, first individual laminations are stamped out, and a certain number of these laminations are stacked, covering one another, until the desired axial width of the core is reached. These stacked laminations form the stator core, which thus on one side has typical teeth and slots, oriented parallel to one another, for a stator. An already prewound core winding, embodied as a distributed wave winding, is in approximately flat form and is then inserted into the slots of the substantially flat core. The flat component unit comprising the core and the core winding has a so-called winding overhang; that is, each individual one of a total of three phases has a winding side which initially is not inserted into slots. This component unit comprising the core and the core winding is then bent round in such a way that a typical hollow-cylindrical stator is created. The overhanging winding sides must finally be inserted into the corresponding slots before the stator is finished.
Because of how it is produced, the core has two ends, which must be placed flush against one another in the round bending of the core with the core winding. These two ends are placed geometrically in the bottom of a core slot.
In this prior art, it is disadvantageous that despite the good access to the slots, the fill factor is not optimal.